In this chapter, you extended your knowledge of using D3 to create a bar graph from a collection of integers. You learned how to position and size each element of the graph according to its data, and how to position groups of data that contain multiple visuals representing a single bar—specifically, how to add a label that represents the value of the underlying datum at the top of a bar.

We then examined the facilities in D3.js for creating axes. We introduced the concept of a scale, which is an important facet of implementing axes. We further examined the different orientations available for an axis, and how to invert the order of the labels on an axis. Finally, we combined the axis and the bar graph together into an effective visualization of the data.

As great as our bar chart looks in this example, we will still have several issues. The overall size of the graph was related to the actual values of the data. This was convenient for demonstrating the construction of a bar graph visualization...